Réalité Enrichie par Synthèse

International audienceIn this paper, a technical solution is presented to automate the mixing of real and synthetic objects in a same animated video sequence. We aim at achieving a close binding between 3D-based analysis and synthesis techniques to compute the interaction between a real scene captured in a sequence of calibrated images, and a computer-generated environment.Nous proposons une méthode pour automatiser l'insertion cohérente d'objets 3D de synthèse dans des séquences d'images réelles. Celle-ci fait appel conjointement à des techniques d'analyse et de synthèse d'images pour calculer les images modifiées

Digital Co-Creation: An Early Stage Product Personalization Methodology to Bridge the User-Designer Void

Modern product development is a complex combination of multidisciplinary processes ranging from market research to design, engineering analysis, and logistics. The product development process has a significant impact on the success or failure of new product launches. The majority of consumer product launches fail, resulting in significant sunk cost in research and development. These failures are commonly due to poor product-market fit which can occur when there is a lack of user involvement in the design process. This background research identified a void between consumer and company which is referred to as the user-designer gap. Mass customization is a form of modern product development that aims to deliver customizable products in an attempt to close the user-designer gap. With a model like this, customers can change material, color, logos, and other modular features on existing products. However, these current mass customization practices fall short of true personalization as they are incapable of adapting form or function of the product to match customer needs. A methodology to address this shortcoming is proposed and is called Digital Co-Creation. Digital Co-Creation aims to harness state-of-art product development tools to create an efficient framework where the user and designer can collaborate to produce a truly personalized product. It does this through two-way communication surrounding results of digital sketching, computer renders, virtual simulations, and augmented reality. This combination of tools to evaluate form and function of the product allow for streamlined development of products with continuous customer feedback. The end result is a product that has been specifically designed and manufactured for the customer at a lower price point than typical bespoke production. A case study was conducted to evaluate the viability of the proposed methodology. For the case study, two contrasting users were presented, and their individual needs were taken into consideration as a unique prosthetic limb was designed for each of them. Finally, the findings were discussed and conclusions about the wider viability of the methodology were made.Key Words: Design Engineering, User-Designer Gap, Product Design, Product Development, Mass Customization, Prostheti

Registration of medical images for applications in minimally invasive procedures

Il punto di partenza di questa tesi \ue8 l'analisi dei metodi allo stato dell'arte di registrazione delle immagini mediche per verificare se sono adatti ad essere utilizzati per assistere il medico durante una procedura minimamente invasiva , ad esempio una procedura percutanea eseguita manualmente o un intervento teleoperato eseguito per mezzo di un robot . La prima conclusione \ue8 che, anche se ci sono tanti lavori dedicati allo sviluppo di algoritmi di registrazione da applicare nel contesto medico, la maggior parte di essi non sono stati progettati per essere utilizzati nello scenario della sala operatoria (OR) anche perch\ue9, rispetto ad altre applicazioni , OR richiede anche la validazione, prestazioni in tempo reale e la presenza di altri strumenti . Gli algoritmi allo stato dell'arte sono basati su un iterazione in tre fasi : ottimizzazione - trasformazione - valutazione della somiglianza delle immagini registrate. In questa tesi, studiamo la fattibilit\ue0 dell'approccio in tre fasi per applicazioni OR, mostrando i limiti che tale approccio incontra nelle applicazioni che stiamo considerando. Verr\ue0 dimostrato come un metodo semplice si potrebbe utilizzare nella OR. Abbiamo poi sviluppato una teoria che \ue8 adatta a registrare grandi insiemi di dati non strutturati estratti da immagini mediche, tenendo conto dei vincoli della OR . Vista l'impossibilit\ue0 di lavorare con dati medici di tipo DICOM, verr\ue0 impiegato un metodo per registrare dataset composti da insiemi di punti non strutturati. Gli algoritmi proposti sono progettati per trovare la corrispondenza spaziale in forma chiusa tenendo conto del tipo di dati, il vincolo del tempo e la presenza di rumore e /o piccole deformazioni. La teoria e gli algoritmi che abbiamo sviluppato sono derivati dalla teoria delle forme proposta da Kendall (Kendall's shapes) e utilizza un descrittore globale della forma per calcolare le corrispondenze e la distanza tra le strutture coinvolte . Poich\ue9 la registrazione \ue8 solo una componente nelle applicazioni mediche, l' ultima parte della tesi \ue8 dedicata ad alcune applicazioni pratiche in OR che possono beneficiare della procedura di registrazione .The registration of medical images is necessary to establish spatial correspondences across two or more images. Registration is rarely the end-goal, but instead, the results of image registration are used in other tasks. The starting point of this thesis is to analyze which methods at the state of the art of image registration are suitable to be used in assisting a physician during a minimally invasive procedure, such as a percutaneous procedure performed manually or a teleoperated intervention performed by the means of a robot. The first conclusion is that, even if much previous work has been devoted to develop registration algorithms to be applied in the medical context, most of them are not designed to be used in the operating room scenario (OR) because, compared to other applications, the OR requires also a strong validation, real-time performance and the presence of other instruments. Almost all of these algorithms are based on a three phase iteration: optimize-transform-evaluate similarity. In this thesis, we study the feasibility of this three steps approach in the OR, showing the limits that such approach encounter in the applications we are considering. We investigate how could a simple method be realizable and what are the assumptions for such a method to work. We then develop a theory that is suitable to register large sets of unstructured data extracted from medical images keeping into account the constraints of the OR. The use of the whole radiologic information is not feasible in the OR context, therefore the method we are introducing registers processed dataset extracted from the original medical images. The framework we propose is designed to find the spatial correspondence in closed form keeping into account the type of the data, the real-time constraint and the presence of noise and/or small deformations. The theory and algorithms we have developed are in the framework of the shape theory proposed by Kendall (Kendall's shapes) and uses a global descriptor of the shape to compute the correspondences and the distance between shapes. Since the registration is only a component of a medical application, the last part of the thesis is dedicated to some practical applications in the OR that can benefit from the registration procedure

Object Calibration for Augmented Reality

Augmented reality involves the use of models and their associated renderings to supplement information in a real scene. In order for this information to be relevant or meaningful, the models must be positioned and displayed in such a way that they align with their corresponding real objects. For practical reasons this alignment cannot be known a priori, and cannot be hard-wired into a system. Instead a simple, reliable alignment or calibration process is performed so that computer models can be accurately registered with their real-life counterparts. We describe the design and implementation of such a process and we show how it can be used to create convincing interactions between real and virtual objects. III 1 Introduction Augmented reality (AR) is a technology in which a user's view (or vision) of the real world is enhanced or augmented with additional information generated from a computer model. In contrast to virtual reality, augmented reality brings the computer into the "world..